Patents by Inventor Stanley G. Stroud

Stanley G. Stroud has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4708204
    Abstract: A system for determining the stuck point of pipe in a borehole including a wireline tool having an exciter coil and a receiver coil axially spaced from one another. The exciter coil is driven at a preselected low frequency and the voltage induced into the receiver coil is related to the magnetic permeability of a pipe through which the tool is run. A receiver coil voltage log is run of the section of pipe in the region of the stuck point first while that region is substantially free of mechanical stress. A second log of the same region is run with the pipe under mechanical stress. Comparison of the two logs determines the stuck point from the difference in magnetic permeability of the stressed pipe above the stuck point and the unstressed pipe below the stuck point.
    Type: Grant
    Filed: September 29, 1986
    Date of Patent: November 24, 1987
    Assignee: NL Industries, Inc.
    Inventor: Stanley G. Stroud